dubbo dubbo-thrift thrift三种协议直观对比
最近在研究学习dubbo源码，下面对比一下dubbo dubbo-thrift thrift三种协议序列化后报文体积：
远程调用一个简单方法：Hello.hello("哈哈哈");
dubbo:{ -38, -69, -62, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -48, 5, 50, 46, 48, 46, 48, 48,
33, 99, 111, 109, 46, 100, 117, 98, 98, 111, 46, 97, 112, 112, 115, 46, 116, 104, 114, 105, 102, 116,
46, 72, 101, 108, 108, 111, 36, 73, 102, 97, 99, 101, 5, 48, 46, 48, 46, 48, 11, 104, 101, 108, 108,
111, 83, 116, 114, 105, 110, 103, 18, 76, 106, 97, 118, 97, 47, 108, 97, 110, 103, 47, 83, 116, 114,
105, 110, 103, 59, 8, -27, -109, -120, -27, -109, -120, 111, 111, 111, 111, 111, 111, 72, 4, 112, 97,
116, 104, 48, 33, 99, 111, 109, 46, 100, 117, 98, 98, 111, 46, 97, 112, 112, 115, 46, 116, 104, 114,
105, 102, 116, 46, 72, 101, 108, 108, 111, 36, 73, 102, 97, 99, 101, 9, 105, 110, 116, 101, 114, 102,
97, 99, 101, 48, 33, 99, 111, 109, 46, 100, 117, 98, 98, 111, 46, 97, 112, 112, 115, 46, 116, 104, 114,
105, 102, 116, 46, 72, 101, 108, 108, 111, 36, 73, 102, 97, 99, 101, 7, 116, 105, 109, 101, 111, 117,
116, 7, 54, 48, 48, 48, 48, 48, 48, 7, 118, 101, 114, 115, 105, 111, 110, 5, 48, 46, 48, 46, 48, 90 };
dubbo_thrift : { 0, 0, 0, 97, -38, -68, 0, 0, 0, 97, 0, 54, 1, 0, 0, 0, 33, 99, 111, 109, 46,
100, 117, 98, 98, 111, 46, 97, 112, 112, 115, 46, 116, 104, 114, 105, 102, 116, 46, 72, 101, 108, 108,
111, 36, 73, 102, 97, 99, 101, 0, 0, 0, 0, 0, 0, 0, 0, -128, 1, 0, 1, 0, 0, 0, 11, 104, 101, 108, 108,
111, 83, 116, 114, 105, 110, 103, 0, 0, 0, 1, 11, 0, 1, 0, 0, 0, 12, -27, -109, -120, -27, -109, -120,
111, 111, 111, 111, 111, 111, 0 };
thrift:{ -128, 1, 0, 1, 0, 0, 0, 11, 104, 101, 108, 108, 111, 83, 116, 114, 105, 110, 103,
0, 0, 0, 1, 11, 0, 1, 0, 0, 0, 12, -27, -109, -120, -27, -109, -120, 111, 111, 111, 111, 111, 111, 0 };显而易见，dubbo协议体积是最大的。实际上，dubbo协议是对hession进行一定的改良。报文体积大的其中一个原因是协议里面附加了较多信息，比如版本号，接口名字，参数类型等。另一个重要原因是dubbo把调用对象或返回结果，直接整个序列化。
dubbo-thrift协议，在thrift原生协议前增加了一些头信息，但信息量不大：
* |<- message header ->|<- message body ->|
* +----------------+----------------------+------------------+---------------------------+-----------------------------------------+
* | magic (2 bytes)|message size (4 bytes)|head size(2 bytes)| version (1 byte) | header | message body |
* +----------------+----------------------+------------------+---------------------------+-----------------------------------------+
* |<- message size ->|